One-turn rectangular loop inductance calculation

The low-frequency inductance of single-turn rectangular loops made of round wire can be estimated accurately with the formula found in [1]; a simpler formula for a limited range of sides ratio was proposed by Rik Strobbe, ON7YD and is compared with the Terman formula and with electromagnetic simulations here.

The Terman formulas are used in the following forms:

RECTANGULAR LOOP OF ROUND WIRE

Rectangle side, s1 : m
Rectangle side, s2 : m
Wire diameter, d : mm

CALCULATED VALUES

Inductance Value, L : µH

Terman has also a formula for the low-frequency inductance of single-turn rectangular loops made of rectangular wire: